Apparatus and methods for solution processing using reverse osmosis

Abstract

Equipment, systems, processes and techniques for conducting reverse osmosis processing of solutions are described. The techniques can be applied to provide diluted solution (i.e. purified solvent), concentrate solution or each. A variety of specific equipment, example systems and processes are depicted and described.

What is claimed is: 
     
         1 . A reverse osmosis system to treat water containing contaminant and produced by a process; the system comprising:
 (a) passing the water through a plurality of selective reverse osmosis membrane units in which the concentration of the contaminant is gradually decreased until clean water is produced.   
     
     
         2 . The reverse osmosis system of  claim 1 , wherein passing the water comprises:
 (a) mixing the water with a first recycle stream of water to create a first water solution;   (b) applying pressure to the first water solution sufficient to past the water solution through a first selective reverse osmosis membrane creating: a solution of salt from that portion of the water solution that did not pass through the first selective reverse osmosis membrane; and, a receiving solution from that portion of the water solution that did pass through the first selective reverse osmosis membrane; the solution of salt being induced by pressure to flow back into the first recycle stream;   (c) mixing the receiving solution with a second recycle stream of water creating a second water solution;   (d) applying pressure to the second water solution sufficient to pass the second water solution through a second selective reverse osmosis membrane creating: a second solution of salt from that portion of the water solution that did not pass through the second selective reverse osmosis membrane; and, a second receiving solution from that portion of the second water solution that did pass through the second selective reverse osmosis membrane; the solution of salt being induced by pressure to flow back into the second recycle stream; and,   (e) continuing to mix the receiving solution with a recycle stream of water and to apply pressure to pass the resulting water solution through additional selective reverse osmosis membranes until the receiving solution is sufficiently diluted that a reverse osmosis unit will produce pure water as a permeate.   
     
     
         3 . The reverse osmosis system of  claim 2  further comprising:
 (a) intermediate surge tanks located between selective reverse osmosis membranes to allow for changes in volume of the receiving solution. 
 
     
     
         4 . A process for treating water with multiple contaminants; the process comprising:
 (a) passing the water through a reverse osmosis system where by the water is treated in a cascading stage-wise manner with one or more selective reverse osmosis membrane units.   
     
     
         5 . The process of  claim 4  wherein the reverse osmosis system comprises:
 (a) passing the water through a plurality of selective reverse osmosis membrane units in which concentration of contaminants is gradually decreased until clean water is produced. 
 
     
     
         6 . The reverse osmosis system of  claim 4 , wherein the passing the water comprises:
 (a) mixing the water with a first recycle stream of water to create a first water solution;   (b) applying pressure to the first water solution sufficient to past the water solution through a first selective reverse osmosis membrane creating: a solution of salt from that portion of the water solution that did not pass through the first selective reverse osmosis membrane; and, a receiving solution from that portion of the water solution that did pass through the first selective reverse osmosis membrane; the solution of salt being induced by pressure to flow back into the first recycle stream;   (c) mixing the receiving solution with a second recycle stream of water creating a second water solution;   (d) applying pressure to the second water solution sufficient to pass the second water solution through a second selective reverse osmosis membrane creating: a second solution of salt from that portion of the water solution that did not pass through the second selective reverse osmosis membrane; and, a second receiving solution from that portion of the second water solution that did pass through the second selective reverse osmosis membrane; the solution of salt being induced by pressure to flow back into the second recycle stream; and,   (e) continuing to mix the receiving solution with a recycle stream of water and to apply pressure to pass the resulting water solution through additional selective reverse osmosis membranes until the receiving solution is sufficiently diluted that a reverse osmosis unit will produce pure water as a permeate.   
     
     
         7 . A reverse osmosis system to treat water containing contaminants and produced from oil and gas drilling comprising:
 passing the water through a plurality of selective membrane unit in which the concentration of contaminants is gradually decreased until clean water is produced.   
     
     
         8 . The reverse osmosis system of  claim 7 , wherein passing the water comprises;
 mixing the water with a first recycle stream of water creating a first water solution;   applying pressure to the water solution sufficient to passing the water, solution through a first selective membrane unit creating a solution of salt from that portion of the water solution that did not pass through the first selective membrane and creating receiving solution from that portion of the water solution that did pass through the first selective membrane, the solution of salt being induced by the pressure to flow back into the recycle stream;   mixing the receiving solution with a second recycle stream of water creating a second water solution;   applying pressure to the second water solution sufficient to passing the second water solution through a second selective membrane unit creating a second solution of salt from that portion of the water solution that did not pass through the second selective membrane and creating a second receiving solution from that portion of the second water solution that did pass through the second selective membrane, the solution of salt being induced by the pressure to flow back into the second recycle stream;   continuing to mix the receiving solution with a recycle stream of water and to apply pressure to pass the resulting water solution through additional selective membrane units until the receiving solution is sufficiently diluted that a standard reverse osmosis until will produce pure water as the permeate.   
     
     
         9 . The reverse osmosis system of  claim 8  further comprises:
 intermediate storage and circulation tanks located between each selective membrane unit to allow for changes in volume of the receiving solution. 
 
     
     
         10 . The reverse osmosis system of  claim 8  wherein the solution of salt is heated under pressure and then removing the water away from the salt by flashed in a low pressure flash vessel producing a dry salt. 
     
     
         11 . A process for treating water with multiple contaminants consisting of:
 filtering the water to remove relatively large particulates;   filtering the water with an oil-coalescing filter to remove immiscible organic fluids;   adjusting the pH and adding components such as sulfates to precipitate heavy metals and the removing the heavy metal salts by filtration;   removing suspended solids and residual organic compounds with an enhanced air flotation device;   passing the water through a reverse osmosis system whereby the water is treated in a cascading stage-wise manner with one or more selective membrane units.   
     
     
         12 . The process of  claim 11 , wherein the reverse osmosis system comprises:
 passing the water through a plurality of selective membrane unit in which the concentration of contaminants is gradually decreased until clean water is produced.   
     
     
         13 . The process of  claim 11 , wherein the reverse osmosis system comprises:
 mixing the water with a first recycle stream of water creating a first water solution;   applying pressure to the water solution sufficient to passing the water solution through a first selective membrane unit creating a solution of salt from that portion of the water solution that did not pass through the first selective membrane and creating receiving solution from that portion of the water solution that did pass through the first selective membrane, the solution of salt being induced by the pressure to flow back into the first recycle stream;   mixing the receiving solution with a second recycle stream of water creating a second water solution;   applying pressure to the second water solution sufficient to passing the second water solution sufficient to passing the second water solution through a second selective membrane unit creating a second solution of salt from that portion of the water solution that did not pass through the second selective membrane and creating a second receiving, solution from that portion of the second water solution that did pass through the second selective membrane, the solution of salt being induced by the pressure to flow back into the second recycle stream;   continuing to mix the receiving solution with a recycle stream of water and to apply pressure to pass the resulting water solution through a selective membrane unit until the receiving solution is sufficiently diluted that a standard reverse osmosis unit will produce pure water as the permeate.